Improvement in valves for steam-pumps



G. W. DIXON. Valve for Steam-Pumps.

Patented Aug. 12, 1879.

as I

INVENTOR ATTORNEYS.

"UNITED STATES. PATENT OF IoE.

GEORGE W. DIXON, OF SPRING LAKE, MICHIGAN.

IMPROVEMENT IN VALVES FOR STEAM-PUMPS.

Specification forming part of Letters Patent No. 218,501, dated August 12, 1879; application filed December 7, 1878.

To all whom it may concern:

Be it known that I, GEORGE W.- DIXON, of Spring Lake, in the county of Ottawa and State of Michigan, have invented a new and useful Improvement in Valves for Direct-Acting Steam-Pumps, of which the following is a specification.

The object of my invention is to simplify the construction of valves for direct-acting steam-pumps, and thereby reduce the first cost of such pumps and the expense of repairs.

My invention consists in a double-seated slide-valve, the same being substantially the ordinary slide-valve fitted within a casein the steam -chest, within which case the valve slides, the space at the ends forming steam-chambers, into which the steam is admitted alternately to move the slide-valve. The admission of steam to the chambers is efiected by means of an auxiliary valve in the steam-chest, which is operated by means of shifting-levers that are acted upon by the piston-head in the enginecylinder.

In the accompanying drawings, Figure 1 is a vertical longitudinal section of an enginecylinder fitted with my improved valve mechanism. Fig. 2 is a plan view with the cover of the steam-chest removed. Fig. 3 is a crosssection on line a; x of Fig. 1. Fig. 4 is a sectional elevation, showing the valve-stem in the cavity of the valve-seat.

Similar letters of reference indicate corresponding parts.

a is the cylinder; 1), the steam-chest. c is the slide-valve, moving upon a valve-seat having parts arranged as usual.

Upon the valve-seat is a case or boxing, d, inclosing slide-valve c tightly at its sides, but permitting it to have the proper movement lengthwise. The valve 0 has a projecting flange, e, at the top, which rests upon the upper edge of case at, which thereby renders valve 0 double-seated.

f is the auxiliary valve fitted in the steamchest outside of box cl, so as to slide and uncover one of the parts 9 g, that are formed in the valve-seat and communicate from the outside to the inside of case d, and at opposite ends of box 01.

The valve f is provided with a stem, h, that projects downward into a cavity, t, in the valve-seat, which cavity communicates with the main exhaust-port k.

In each cylinder-head, in a suitable recess, is fulcrumed a shifting-lever, l, in such position that each leverl will be acted upon by the piston-head in its turn at the completion of the stroke.

m m are rods fitted in the upper part of cylinder a, at opposite sides of the stem h of valve f, in a position to be acted upon by the levers l and .move valve f either in one direction or the other, according to the direction in which the piston is moving. Each rod m is fitted with a collar, n, that acts as a valve to prevent passage of steam through the holes in which the rods are placed.

The under side of valve fis recessed, as seen at 0, Fig. 4, to form exhaust-ports in connection with ports 9 and opening '5. as hereinafter described.

When the valve f is shifted by the action of the piston-head upon lever l, as described, port 9 is covered by f, and the steam enters the other port, g, and goes between the end of valve 0 and case d, and forces valve 0 to the other end of box d, which action changes the relative positions of the main ports. Upon the return stroke of the piston, valve f is again shifted, the other port, 9, uncovered, and valve 0 moved in the opposite direction. As soon as valve f is shifted, the recess 0 coincides with port 9 and permits the escape of the steam from that end of box 01.

The mechanism described has but few parts, and those are of simple construction, such as can be repaired by any mechanic familiar with the ordinary valve mechanism of steam-engines.

Having thus described my invention, I claim as new and desire to secure by Letters Patent 1. In combination with the cylinder and steam-chest having ports, substantially as described and shown, the valve 0, having flange e, overlapping case d, and valve f, the valve f being shifted by the movement of the pistonhead through positive connections, substantially as described and shown.

2. The combination, withthe main valve,

the auxiliary valve f, having the stem h, the I valve f, rods m, and shifting-levers I, combined, valve-seat having the cavity 1', and the main arranged, and operating substantially as deexhaust-port k, of the levers I, fulcrulned in scribed and shown, and for the purposes set cylinder-heads, and the rods m, having the forth.

332355 substantlally as and for the purpose GEORGE W. DIXON 3. In combination with a cylimlerand steam- Witnesses: chest having ports, snbstantiallya-s described ROBERT M. DONALD,

and shown, the ease (I, double-seated valve 0, CHAS. M. KAY. 

